The invention relates to a sensor arrangement comprising two sensors and a processing circuit, having two A/D converter units each receiving a sensor signal from one of the sensors to an angular-position sensor arrangement comprising two angular-position sensors which are angularly spaced from one another and a similar processing unit, and to a method of measurement-error detection for such a sensor arrangement.
Such a sensor arrangement is known from the Philips Data Handbook SC 17, Semiconductor Sensors, 1997, pages 186-187. In said arrangement two angular-position sensors are each connected to an A/D converter unit (A/D=analog/digital). The angular-position sensors, which each comprise four measuring elements in a bridge arrangement, are spaced at an angle of 45.degree. from one another and each produce a sinusoidal sensor signal on the output. As a result of the angularly spaced arrangement these sensor signals are 90.degree. phase-shifted. By means of a processing unit a measurement signal is determined, which is for example proportional to the angular position of a measurement object relative to the sensor arrangement.
It has been found that on the input of the processing unit, particularly during the A/D conversion of the sensor signals, errors can occur which invalidate the measurement signal to be determined without this being detectable from the measurement signal or the sensor signals in the known sensor arrangement. Such errors can be caused, for example, by a faulty A/D converter unit. Moreover, the sensors themselves may operate incorrectly.